1 /*	$NetBSD: vfs_syscalls_43.c,v 1.57 2014/09/05 09:21:54 matt Exp $	*/
2 
3 /*
4  * Copyright (c) 1989, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  * (c) UNIX System Laboratories, Inc.
7  * All or some portions of this file are derived from material licensed
8  * to the University of California by American Telephone and Telegraph
9  * Co. or Unix System Laboratories, Inc. and are reproduced herein with
10  * the permission of UNIX System Laboratories, Inc.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions and the following disclaimer.
17  * 2. Redistributions in binary form must reproduce the above copyright
18  *    notice, this list of conditions and the following disclaimer in the
19  *    documentation and/or other materials provided with the distribution.
20  * 3. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  *
36  *	@(#)vfs_syscalls.c	8.28 (Berkeley) 12/10/94
37  */
38 
39 #include <sys/cdefs.h>
40 __KERNEL_RCSID(0, "$NetBSD: vfs_syscalls_43.c,v 1.57 2014/09/05 09:21:54 matt Exp $");
41 
42 #if defined(_KERNEL_OPT)
43 #include "opt_compat_netbsd.h"
44 #endif
45 
46 #include <sys/param.h>
47 #include <sys/systm.h>
48 #include <sys/filedesc.h>
49 #include <sys/kernel.h>
50 #include <sys/proc.h>
51 #include <sys/file.h>
52 #include <sys/vnode.h>
53 #include <sys/namei.h>
54 #include <sys/dirent.h>
55 #include <sys/socket.h>
56 #include <sys/socketvar.h>
57 #include <sys/stat.h>
58 #include <sys/malloc.h>
59 #include <sys/ioctl.h>
60 #include <sys/fcntl.h>
61 #include <sys/sysctl.h>
62 #include <sys/syslog.h>
63 #include <sys/unistd.h>
64 #include <sys/resourcevar.h>
65 #include <sys/sysctl.h>
66 
67 #include <sys/mount.h>
68 #include <sys/syscallargs.h>
69 #include <sys/vfs_syscalls.h>
70 
71 #include <compat/sys/stat.h>
72 #include <compat/sys/mount.h>
73 #include <compat/sys/dirent.h>
74 
75 #include <compat/common/compat_util.h>
76 #include <compat/common/compat_mod.h>
77 
78 static void cvtstat(struct stat *, struct stat43 *);
79 
80 /*
81  * Convert from an old to a new stat structure.
82  */
83 static void
cvtstat(struct stat * st,struct stat43 * ost)84 cvtstat(struct stat *st, struct stat43 *ost)
85 {
86 
87 	ost->st_dev = st->st_dev;
88 	ost->st_ino = st->st_ino;
89 	ost->st_mode = st->st_mode & 0xffff;
90 	ost->st_nlink = st->st_nlink;
91 	ost->st_uid = st->st_uid;
92 	ost->st_gid = st->st_gid;
93 	ost->st_rdev = st->st_rdev;
94 	if (st->st_size < (quad_t)1 << 32)
95 		ost->st_size = st->st_size;
96 	else
97 		ost->st_size = -2;
98 	ost->st_atime = st->st_atime;
99 	ost->st_mtime = st->st_mtime;
100 	ost->st_ctime = st->st_ctime;
101 	ost->st_blksize = st->st_blksize;
102 	ost->st_blocks = st->st_blocks;
103 	ost->st_flags = st->st_flags;
104 	ost->st_gen = st->st_gen;
105 }
106 
107 /*
108  * Get file status; this version follows links.
109  */
110 /* ARGSUSED */
111 int
compat_43_sys_stat(struct lwp * l,const struct compat_43_sys_stat_args * uap,register_t * retval)112 compat_43_sys_stat(struct lwp *l, const struct compat_43_sys_stat_args *uap, register_t *retval)
113 {
114 	/* {
115 		syscallarg(char *) path;
116 		syscallarg(struct stat43 *) ub;
117 	} */
118 	struct stat sb;
119 	struct stat43 osb;
120 	int error;
121 
122 	error = do_sys_stat(SCARG(uap, path), FOLLOW, &sb);
123 	if (error)
124 		return (error);
125 	cvtstat(&sb, &osb);
126 	error = copyout((void *)&osb, (void *)SCARG(uap, ub), sizeof (osb));
127 	return (error);
128 }
129 
130 /*
131  * Get file status; this version does not follow links.
132  */
133 /* ARGSUSED */
134 int
compat_43_sys_lstat(struct lwp * l,const struct compat_43_sys_lstat_args * uap,register_t * retval)135 compat_43_sys_lstat(struct lwp *l, const struct compat_43_sys_lstat_args *uap, register_t *retval)
136 {
137 	/* {
138 		syscallarg(char *) path;
139 		syscallarg(struct ostat *) ub;
140 	} */
141 	struct vnode *vp, *dvp;
142 	struct stat sb, sb1;
143 	struct stat43 osb;
144 	int error;
145 	struct pathbuf *pb;
146 	struct nameidata nd;
147 	int ndflags;
148 
149 	error = pathbuf_copyin(SCARG(uap, path), &pb);
150 	if (error) {
151 		return error;
152 	}
153 
154 	ndflags = NOFOLLOW | LOCKLEAF | LOCKPARENT | TRYEMULROOT;
155 again:
156 	NDINIT(&nd, LOOKUP, ndflags, pb);
157 	if ((error = namei(&nd))) {
158 		if (error == EISDIR && (ndflags & LOCKPARENT) != 0) {
159 			/*
160 			 * Should only happen on '/'. Retry without LOCKPARENT;
161 			 * this is safe since the vnode won't be a VLNK.
162 			 */
163 			ndflags &= ~LOCKPARENT;
164 			goto again;
165 		}
166 		pathbuf_destroy(pb);
167 		return (error);
168 	}
169 	/*
170 	 * For symbolic links, always return the attributes of its
171 	 * containing directory, except for mode, size, and links.
172 	 */
173 	vp = nd.ni_vp;
174 	dvp = nd.ni_dvp;
175 	pathbuf_destroy(pb);
176 	if (vp->v_type != VLNK) {
177 		if ((ndflags & LOCKPARENT) != 0) {
178 			if (dvp == vp)
179 				vrele(dvp);
180 			else
181 				vput(dvp);
182 		}
183 		error = vn_stat(vp, &sb);
184 		vput(vp);
185 		if (error)
186 			return (error);
187 	} else {
188 		error = vn_stat(dvp, &sb);
189 		vput(dvp);
190 		if (error) {
191 			vput(vp);
192 			return (error);
193 		}
194 		error = vn_stat(vp, &sb1);
195 		vput(vp);
196 		if (error)
197 			return (error);
198 		sb.st_mode &= ~S_IFDIR;
199 		sb.st_mode |= S_IFLNK;
200 		sb.st_nlink = sb1.st_nlink;
201 		sb.st_size = sb1.st_size;
202 		sb.st_blocks = sb1.st_blocks;
203 	}
204 	cvtstat(&sb, &osb);
205 	error = copyout((void *)&osb, (void *)SCARG(uap, ub), sizeof (osb));
206 	return (error);
207 }
208 
209 /*
210  * Return status information about a file descriptor.
211  */
212 /* ARGSUSED */
213 int
compat_43_sys_fstat(struct lwp * l,const struct compat_43_sys_fstat_args * uap,register_t * retval)214 compat_43_sys_fstat(struct lwp *l, const struct compat_43_sys_fstat_args *uap, register_t *retval)
215 {
216 	/* {
217 		syscallarg(int) fd;
218 		syscallarg(struct stat43 *) sb;
219 	} */
220 	struct stat ub;
221 	struct stat43 oub;
222 	int error;
223 
224 	error = do_sys_fstat(SCARG(uap, fd), &ub);
225 	if (error == 0) {
226 		cvtstat(&ub, &oub);
227 		error = copyout((void *)&oub, (void *)SCARG(uap, sb),
228 		    sizeof (oub));
229 	}
230 
231 	return (error);
232 }
233 
234 
235 /*
236  * Truncate a file given a file descriptor.
237  */
238 /* ARGSUSED */
239 int
compat_43_sys_ftruncate(struct lwp * l,const struct compat_43_sys_ftruncate_args * uap,register_t * retval)240 compat_43_sys_ftruncate(struct lwp *l, const struct compat_43_sys_ftruncate_args *uap, register_t *retval)
241 {
242 	/* {
243 		syscallarg(int) fd;
244 		syscallarg(long) length;
245 	} */
246 	struct sys_ftruncate_args /* {
247 		syscallarg(int) fd;
248 		syscallarg(int) pad;
249 		syscallarg(off_t) length;
250 	} */ nuap;
251 
252 	SCARG(&nuap, fd) = SCARG(uap, fd);
253 	SCARG(&nuap, length) = SCARG(uap, length);
254 	return (sys_ftruncate(l, &nuap, retval));
255 }
256 
257 /*
258  * Truncate a file given its path name.
259  */
260 /* ARGSUSED */
261 int
compat_43_sys_truncate(struct lwp * l,const struct compat_43_sys_truncate_args * uap,register_t * retval)262 compat_43_sys_truncate(struct lwp *l, const struct compat_43_sys_truncate_args *uap, register_t *retval)
263 {
264 	/* {
265 		syscallarg(char *) path;
266 		syscallarg(long) length;
267 	} */
268 	struct sys_truncate_args /* {
269 		syscallarg(char *) path;
270 		syscallarg(int) pad;
271 		syscallarg(off_t) length;
272 	} */ nuap;
273 
274 	SCARG(&nuap, path) = SCARG(uap, path);
275 	SCARG(&nuap, length) = SCARG(uap, length);
276 	return (sys_truncate(l, &nuap, retval));
277 }
278 
279 
280 /*
281  * Reposition read/write file offset.
282  */
283 int
compat_43_sys_lseek(struct lwp * l,const struct compat_43_sys_lseek_args * uap,register_t * retval)284 compat_43_sys_lseek(struct lwp *l, const struct compat_43_sys_lseek_args *uap, register_t *retval)
285 {
286 	/* {
287 		syscallarg(int) fd;
288 		syscallarg(long) offset;
289 		syscallarg(int) whence;
290 	} */
291 	struct sys_lseek_args /* {
292 		syscallarg(int) fd;
293 		syscallarg(int) pad;
294 		syscallarg(off_t) offset;
295 		syscallarg(int) whence;
296 	} */ nuap;
297 	off_t qret;
298 	int error;
299 
300 	SCARG(&nuap, fd) = SCARG(uap, fd);
301 	SCARG(&nuap, offset) = SCARG(uap, offset);
302 	SCARG(&nuap, whence) = SCARG(uap, whence);
303 	error = sys_lseek(l, &nuap, (register_t *)&qret);
304 	*(long *)retval = qret;
305 	return (error);
306 }
307 
308 
309 /*
310  * Create a file.
311  */
312 int
compat_43_sys_creat(struct lwp * l,const struct compat_43_sys_creat_args * uap,register_t * retval)313 compat_43_sys_creat(struct lwp *l, const struct compat_43_sys_creat_args *uap, register_t *retval)
314 {
315 	/* {
316 		syscallarg(char *) path;
317 		syscallarg(int) mode;
318 	} */
319 	struct sys_open_args /* {
320 		syscallarg(char *) path;
321 		syscallarg(int) flags;
322 		syscallarg(int) mode;
323 	} */ nuap;
324 
325 	SCARG(&nuap, path) = SCARG(uap, path);
326 	SCARG(&nuap, mode) = SCARG(uap, mode);
327 	SCARG(&nuap, flags) = O_WRONLY | O_CREAT | O_TRUNC;
328 	return (sys_open(l, &nuap, retval));
329 }
330 
331 /*ARGSUSED*/
332 int
compat_43_sys_quota(struct lwp * l,const void * v,register_t * retval)333 compat_43_sys_quota(struct lwp *l, const void *v, register_t *retval)
334 {
335 
336 	return (ENOSYS);
337 }
338 
339 
340 /*
341  * Read a block of directory entries in a file system independent format.
342  */
343 int
compat_43_sys_getdirentries(struct lwp * l,const struct compat_43_sys_getdirentries_args * uap,register_t * retval)344 compat_43_sys_getdirentries(struct lwp *l, const struct compat_43_sys_getdirentries_args *uap, register_t *retval)
345 {
346 	/* {
347 		syscallarg(int) fd;
348 		syscallarg(char *) buf;
349 		syscallarg(u_int) count;
350 		syscallarg(long *) basep;
351 	} */
352 	struct dirent *bdp;
353 	struct vnode *vp;
354 	void *tbuf;			/* Current-format */
355 	char *inp;			/* Current-format */
356 	int len, reclen;		/* Current-format */
357 	char *outp;			/* Dirent12-format */
358 	int resid, old_reclen = 0;	/* Dirent12-format */
359 	struct file *fp;
360 	struct uio auio;
361 	struct iovec aiov;
362 	struct dirent43 idb;
363 	off_t off;		/* true file offset */
364 	int buflen, error, eofflag, nbytes;
365 	struct vattr va;
366 	off_t *cookiebuf = NULL, *cookie;
367 	int ncookies;
368 	long loff;
369 
370 	/* fd_getvnode() will use the descriptor for us */
371 	if ((error = fd_getvnode(SCARG(uap, fd), &fp)) != 0)
372 		return (error);
373 
374 	if ((fp->f_flag & FREAD) == 0) {
375 		error = EBADF;
376 		goto out1;
377 	}
378 
379 	vp = fp->f_vnode;
380 	if (vp->v_type != VDIR) {
381 		error = ENOTDIR;
382 		goto out1;
383 	}
384 
385 	vn_lock(vp, LK_SHARED | LK_RETRY);
386 	error = VOP_GETATTR(vp, &va, l->l_cred);
387 	VOP_UNLOCK(vp);
388 	if (error)
389 		goto out1;
390 
391 	loff = fp->f_offset;
392 	nbytes = SCARG(uap, count);
393 	buflen = min(MAXBSIZE, nbytes);
394 	if (buflen < va.va_blocksize)
395 		buflen = va.va_blocksize;
396 	tbuf = malloc(buflen, M_TEMP, M_WAITOK);
397 
398 	vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
399 	off = fp->f_offset;
400 again:
401 	aiov.iov_base = tbuf;
402 	aiov.iov_len = buflen;
403 	auio.uio_iov = &aiov;
404 	auio.uio_iovcnt = 1;
405 	auio.uio_rw = UIO_READ;
406 	auio.uio_resid = buflen;
407 	auio.uio_offset = off;
408 	UIO_SETUP_SYSSPACE(&auio);
409 	/*
410          * First we read into the malloc'ed buffer, then
411          * we massage it into user space, one record at a time.
412          */
413 	error = VOP_READDIR(vp, &auio, fp->f_cred, &eofflag, &cookiebuf,
414 	    &ncookies);
415 	if (error)
416 		goto out;
417 
418 	inp = (char *)tbuf;
419 	outp = SCARG(uap, buf);
420 	resid = nbytes;
421 	if ((len = buflen - auio.uio_resid) == 0)
422 		goto eof;
423 
424 	for (cookie = cookiebuf; len > 0; len -= reclen) {
425 		bdp = (struct dirent *)inp;
426 		reclen = bdp->d_reclen;
427 		if (reclen & 3)
428 			panic(__func__);
429 		if (bdp->d_fileno == 0) {
430 			inp += reclen;	/* it is a hole; squish it out */
431 			if (cookie)
432 				off = *cookie++;
433 			else
434 				off += reclen;
435 			continue;
436 		}
437 		old_reclen = _DIRENT_RECLEN(&idb, bdp->d_namlen);
438 		if (reclen > len || resid < old_reclen) {
439 			/* entry too big for buffer, so just stop */
440 			outp++;
441 			break;
442 		}
443 		/*
444 		 * Massage in place to make a Dirent12-shaped dirent (otherwise
445 		 * we have to worry about touching user memory outside of
446 		 * the copyout() call).
447 		 */
448 		idb.d_fileno = (uint32_t)bdp->d_fileno;
449 		idb.d_reclen = (uint16_t)old_reclen;
450 		idb.d_namlen = (uint16_t)bdp->d_namlen;
451 		strcpy(idb.d_name, bdp->d_name);
452 		if ((error = copyout(&idb, outp, old_reclen)))
453 			goto out;
454 		/* advance past this real entry */
455 		inp += reclen;
456 		if (cookie)
457 			off = *cookie++; /* each entry points to itself */
458 		else
459 			off += reclen;
460 		/* advance output past Dirent12-shaped entry */
461 		outp += old_reclen;
462 		resid -= old_reclen;
463 	}
464 
465 	/* if we squished out the whole block, try again */
466 	if (outp == SCARG(uap, buf)) {
467 		if (cookiebuf)
468 			free(cookiebuf, M_TEMP);
469 		cookiebuf = NULL;
470 		goto again;
471 	}
472 	fp->f_offset = off;	/* update the vnode offset */
473 
474 eof:
475 	*retval = nbytes - resid;
476 out:
477 	VOP_UNLOCK(vp);
478 	if (cookiebuf)
479 		free(cookiebuf, M_TEMP);
480 	free(tbuf, M_TEMP);
481 out1:
482 	fd_putfile(SCARG(uap, fd));
483 	if (error)
484 		return error;
485 	return copyout(&loff, SCARG(uap, basep), sizeof(long));
486 }
487 
488 /*
489  * sysctl helper routine for vfs.generic.conf lookups.
490  */
491 #if defined(COMPAT_09) || defined(COMPAT_43) || defined(COMPAT_44)
492 
493 static int
sysctl_vfs_generic_conf(SYSCTLFN_ARGS)494 sysctl_vfs_generic_conf(SYSCTLFN_ARGS)
495 {
496         struct vfsconf vfc;
497         extern const char * const mountcompatnames[];
498         extern int nmountcompatnames;
499 	struct sysctlnode node;
500 	struct vfsops *vfsp;
501 	u_int vfsnum;
502 
503 	if (namelen != 1)
504 		return (ENOTDIR);
505 	vfsnum = name[0];
506 	if (vfsnum >= nmountcompatnames ||
507 	    mountcompatnames[vfsnum] == NULL)
508 		return (EOPNOTSUPP);
509 	vfsp = vfs_getopsbyname(mountcompatnames[vfsnum]);
510 	if (vfsp == NULL)
511 		return (EOPNOTSUPP);
512 
513 	vfc.vfc_vfsops = vfsp;
514 	strncpy(vfc.vfc_name, vfsp->vfs_name, sizeof(vfc.vfc_name));
515 	vfc.vfc_typenum = vfsnum;
516 	vfc.vfc_refcount = vfsp->vfs_refcount;
517 	vfc.vfc_flags = 0;
518 	vfc.vfc_mountroot = vfsp->vfs_mountroot;
519 	vfc.vfc_next = NULL;
520 	vfs_delref(vfsp);
521 
522 	node = *rnode;
523 	node.sysctl_data = &vfc;
524 	return (sysctl_lookup(SYSCTLFN_CALL(&node)));
525 }
526 
527 /*
528  * Top level filesystem related information gathering.
529  */
530 void
compat_sysctl_vfs(struct sysctllog ** clog)531 compat_sysctl_vfs(struct sysctllog **clog)
532 {
533 	extern int nmountcompatnames;
534 
535 	sysctl_createv(clog, 0, NULL, NULL,
536 		       CTLFLAG_PERMANENT|CTLFLAG_IMMEDIATE,
537 		       CTLTYPE_INT, "maxtypenum",
538 		       SYSCTL_DESCR("Highest valid filesystem type number"),
539 		       NULL, nmountcompatnames, NULL, 0,
540 		       CTL_VFS, VFS_GENERIC, VFS_MAXTYPENUM, CTL_EOL);
541 	sysctl_createv(clog, 0, NULL, NULL,
542 		       CTLFLAG_PERMANENT,
543 		       CTLTYPE_STRUCT, "conf",
544 		       SYSCTL_DESCR("Filesystem configuration information"),
545 		       sysctl_vfs_generic_conf, 0, NULL,
546 		       sizeof(struct vfsconf),
547 		       CTL_VFS, VFS_GENERIC, VFS_CONF, CTL_EOL);
548 }
549 #endif
550